docs: add JDLT to the company list (#1345)

Introduces a new company with its logo and link in the list of
partners.
Includes an SVG asset for the visual representation of JDLT.

Author: jakedee

src/assets/we-are-using/jdlt.svg

@@ -277,6 +277,11 @@ const companies = [
 		name: 'Loveholidays',
 		href: 'https://loveholidays.com',
 		logo: 'loveholidays.svg'
+	},
+	{
+		name: 'JDLT',
+		href: 'https://jdlt.co.uk',
+		logo: 'jdlt.svg'
 	}
 ];